var list = [{
        '2018-05-14': [{
            uid: 171677,
            amount: 413,
            mobileNum: "185******58",
            userName: "b**"
        }, {
            uid: 171618,
            amount: 222,
            mobileNum: "199******01",
            userName: "王**"
        }, ]
    },
    {
        '2018-05-15': [{
            uid: 171677,
            amount: 413,
            mobileNum: "185******58",
            userName: "张**"
        }, {
            uid: 171618,
            amount: 222,
            mobileNum: "169******01",
            userName: "杨**"
        }]
    }
]

console.log(list);

function p(s) {
    return s < 10 ? '0' + s : s;
}
var myDate = new Date();
var year = myDate.getFullYear(); //获取当前年
var month = myDate.getMonth() + 1; //获取当前月
var date = myDate.getDate(); //获取当前日
var today = year + '-' + p(month) + "-" + p(date);

var todayIndex;
var toIndex = -1;
var key; // 属性名
var todayArray; // 要展示的数组
for (var i = 0; i < list.length; i++) {

    for (key in list[i]) {
        console.log(key); // 获取到每一个数组的属性名
        console.log(list[i][key])
        if (key == today) { //判断判断当天是否存在于数组内
            toIndex = i;
            todayArray = list[i][key];
            break;
        }
    }
    todayIndex = toIndex;
}
console.log('todayIndex=' + todayIndex);
console.log('todayArray=' + todayArray);
if (todayIndex >= 0) { // 判断当天是否存在于数组内
    if (todayArray.length > 0) { // 判断当天是否有数据
        for (var i = 0; i < todayArray.length; i++) {
            console.log('-----------------------------');
            console.log('uid=' + todayArray[i].uid);
            console.log('amount=' + todayArray[i].amount);
            console.log('mobileNum=' + todayArray[i].mobileNum);
            console.log('userName=' + todayArray[i].userName);
            console.log('-----------------------------');
        }
    } else {
        console.error('当天暂时没有排名');
    }
} else {
    // 这里是当天时间 不存在于 数组内
    console.error('不在活动期间');
}